Filter quantities per product option

[ipapachristoudis]

Hello

I am an intermediate java developer and in the past I have successfully developed two e-shops based on konakart framework, community edition.
Currently, i am working on a new project and i have come up to a problem with an implementation requirement.
The e-shop must have various filters (search facets???) for showing products based on product-options quantities.
As an example, you can visit http://www.myshoe.gr/andrika/andrika-papoytsia_s-66911.aspx where you can see the "ΜΕΓΕΘΟΣ" filter, showing sizes available for all models (with quantities>0).
After reading the documentation, i though that this could be achieved by using custom attributes, but later i wasn't sure.
As an example, the store at the beginning will have 10 t-shirt models, four sizes (SM,M,L,XL) and 2 pieces per quantity for every model. I have understand the way to configure these is by using products options.
The requested search facet should have all sizes and when  the user selects one size, products should be searched and returned those that at that time have quantities>0 for that size.
I have understand that for using extra facets i need the products custom features, but i am not sure that the above functionality can be achieved, because (forgive me if i am wrong) quantities are not supported through custom attributes.
Can you give me some hints?

[julie]

I think you could do what you require if you used the EE version of KK with the Solr search engine.
When adding products to Solr you would need to add code to one of the customization points in order to index a product for each size. When searching for products you would need to set the quantityGreaterThan attribute in the product search object to only find products with a quantity greater than zero.